A device provided with such characteristics is known for example from Italian Utility Model Application PN2004U000013.
In the technical field of sports footwear, including in particular cycling footwear, there is a need to adjust the fastening tension rapidly, even while in motion. This adjustment, with particular reference to the closure of the instep region of the footwear, where this locks on the back of the foot, serves adequately to address specific pedalling circumstances, different for example when pedalling uphill from when pedalling on the flat or downhill.
The adjustment must allow maximum clamping of the foot without however causing soreness. To this end, various devices have been developed which make it possible to carry out such adjustment, starting from a state of complete clamping of the foot, by releasing the toothed strap a little at a time. These mechanisms, including that described in the patent application cited previously, have some drawbacks however, not least the fact that the closeness of the controls for controlled release and total release may lead to the accidental total release of the fastening. Furthermore, the total release of the fastening, when obtained by pressing the corresponding push-button towards the base, may be hindered or even blocked in the presence of mud or dirt between the fastening and the strap.
A further drawback arises from the fact that the hooking means of the ratchet is not hinged directly on the base, and this may entail possible malfunctions under load.
The problem underlying the present invention is that of providing a fastening device structurally and functionally designed so as to remedy all the drawbacks mentioned with reference to the prior art cited.